1. Field of the Invention
The present invention relates to an on-board type connector which is adapted to be mounted on a circuit board.
2. Description of the Related Art
Generally, the on-board type connector is constructed in such a manner that its terminals are respectively provided with leg portions, and the leg portions are connected to and fixed on the circuit board by soldering or so. However, with such fixation of the connector only by means of soldering between the leg portions of the terminals and the circuit board, high connection reliability cannot be obtained, because an outer force exerted on the relevant connector will be transferred as it is, to the soldered parts (terminal connecting parts) and will cause a large overload in strength on the soldered parts. In view of the circumstances, it has been considered heretofore to decrease the overload in strength by fixing a reinforcing metal to a housing of the connector, and fixing this metal on the circuit board by soldering or so independently of the terminals.
One example of such a structure is shown in FIGS. 9 to 11. A connector illustrated on the drawings is intended to electrically connect a flat wiring member 40 which is flat and flexible, to a circuit board C as shown in FIG. 10. The connector includes a number of terminals 10, a housing 20 for holding the terminals, and a slider 30 attached to this housing 20.
Each of the terminals 10 is formed of conductive material such as metal, and integrally has a leg portion 12 in a substantially L-shape which is mounted on the circuit board C as shown in FIG. 10, an upper horizontal portion 14 horizontally extending from an upper end of the leg portion 12, a lower horizontal portion 16 branched off downward from a base end of the upper horizontal portion 14 and extending in parallel to the upper horizontal portion 14, and a conductor contacting portion 18 which is turned back from an end of the lower horizontal portion 16 at an acute angle. These terminals 10 are held by the housing 20 in such a manner that they are directed in a back and forth direction and arranged in a row in a lateral direction.
The housing 20 is integrally molded of synthetic resin in its entirety, and has a body part 21 which extends laterally, and a top wall part 22 which extends in parallel to the body part 21 above a backward half part of the body part 21. These body part 21 and top wall part 22 are connected vertically at a back part, and left and right sides of the housing. The body part 21 is formed with terminal containing grooves 21a extending in a back and forth direction which are adapted to contain the lower horizontal portions 16 of the aforesaid terminals 10, so that the conductor contacting portions 18 of the terminals 10 may project upward from the terminal containing grooves 21a. There are formed, on a lower face of the top wall part 22, terminal insertion grooves 22a into which the upper horizontal portions 14 of the terminals 10 are respectively inserted.
The slider 30 is also integrally formed of insulating material, and has a shape of extending in a lateral direction of the flat wiring member 40. More specifically, the slider 30 integrally has a pair of left and right side walls 32 extending in a back and forth direction, and a laterally extending connecting part 34 which connects both the side walls 32. A wiring member holding piece 35 extends backward from the connecting part 34. There are further formed, on inner faces of both the side walls 32, lockable portions 36 which project inwardly.
On the other hand, at an end of the flat wiring member 40 to be inserted into the housing 20, an insulating layer on its lower face is peeled off to expose an inner conductor at its lower side, and a reinforcing plate 42 is fixed to an upper face of the end by means of boding or the like.
In a state where the slider 30 has been completely withdrawn forward from the housing 20, the end of the flat wiring member 40 is inserted into a space between the upper horizontal portion 14 and the conductor contacting portion 18 of the terminal 10 in the housing 20, from underneath of the connecting part 34 and the wiring member holding piece 35 of the slider 30. Thereafter, the slider 30 is pushed into the housing 20 toward its backward end, and comes into a state where the wiring member holding piece 35 of the slider 30 has pressed the end of the flat wiring member 40 onto an upper side of the conductor contacting portion 18, as shown in FIG. 10. In this manner, the exposed portion of the conductor at the end of the flat wiring member is press contacted with the conductor contacting portion 18, and both the members are electrically connected. When the slider 30 has been completely inserted, the lockable portions 36 come into engagement with the locking projections 28 provided on the side walls of the housing 20, thereby to retain the slider 30 from dropping.
It is intended with this connector that a pair of left and right metal plates 50 for reinforcement as shown in FIGS. 11A and 11B are fixed to this connector. Each of the reinforcing metal plates 50 is formed of a single metal plate by bending work, and integrally has a part 51 to be fixed on the circuit board C, and apart 52 to be fixed to the housing which is erected upward from a side of a backward end of the part 51 to be fixed on the board. There is formed a cut-out 52a at a middle position of a front edge of the part 52 to be fixed to the housing.
On the other hand, at both ends in a lateral direction of the housing 20, there are formed backwardly opening slits 23 along an entire length of the housing 20 in a vertical direction. At a middle position of each of the slits 23, there is formed a backwardly projecting projection 23a. 
By press fitting the parts 52 of the reinforcing metal plate 50 to be fixed to the housing into the slits 23 from the back side (in other words, by press fitting the projections 23a into the cut-outs 52a), the reinforcing metal plate 50 is fixed to the housing 20. Then, by fixing the parts 51 to be fixed on the board in this reinforcing metal plate 50 to the circuit board C which is not shown in the drawing, by soldering or so, the overload in strength exerted on the connecting positions between the leg portions of the terminals 10 and the circuit board C can be reduced.
Recently, the above described connector, particularly the connector for an automobile has come to have multi-contacts, and accordingly, requires a larger force than ever for inserting and detaching the slider 30 as described above or a connector to be mated. In the conventional connector as described above, the parts 52 of the reinforcing metal plate 50 to be fixed to the housing are inserted into the slits 23 of the housing 20 from the back side. Accordingly, it is difficult to withstand a force of pulling the housing 20 forward, that is, a force exerted on the housing 20 (a leftward force in FIGS. 11A and 11B) when the slider 30 is extracted from the relevant connector (when the relevant connector is detached in case where the connector is to be mated), and there is a fear that the force may exert a large overload on the connecting positions between the leg portions of the terminals 10 and the circuit board C.
In view of the above described circumstances, it is an object of the invention to provide an on-board type connector which is simple in structure, and in which an overload in strength exerted on connecting positions between terminals and a circuit board can be effectively reduced, even when a slider or a connector to be mated is connected to or detached from a housing.
To solve the above described problems, there is provided according to the invention, an on-board type connector comprising a housing made of synthetic resin which holds a plurality of terminals to be connected to a circuit board in such a manner that the terminals are directed in a back and forth direction and laterally arranged, and two reinforcing metal plates fixed to both sides of the housing in a lateral direction, the reinforcing metal plates integrally having parts to be fixed to both sides of the housing made of synthetic resin in the lateral direction and parts to be fixed on the circuit board, characterized in that the housing is provided, at both sides thereof in the lateral direction, with insertion slits which open toward a bottom face of the housing, and into which the parts to be fixed to the housing are inserted from the bottom face and fixed, the insertion slits being so shaped that the parts to be fixed to the housing which have been inserted into the slits are restrained by the housing from both a front and a back sides.
According to this structure, the overload in strength exerted on the connecting positions between the relevant circuit board and the terminals can be reduced, by fixing the parts of the reinforcing metal plates to be fixed on the circuit board on the relevant circuit board in a state where the reinforcing metal plates are inserted into the insertion slits which are formed in the housing and fixed. Moreover, the insertion slits open toward the bottom face of the housing, and the parts to be fixed to the housing are inserted from the bottom face and fixed, to be restrained by the housing from both the front and the back sides. Therefore, an outer force applied to the terminals and the housing when the slider or the connector to be mated is inserted or detached can be sufficiently withstood, and the overload in strength exerted on the connecting positions between the terminals and the circuit board can be effectively reduced.
More specifically, it is preferable that the parts of the reinforcing metal plate to be fixed to the housing may be formed at both sides of the relevant reinforcing metal plate in a back and forth direction, while the insertion slits may be formed at both forward and backward sides of the housing, and a restraining part adapted to restrain the parts to be fixed to the housing from inside may be formed at an intermediate position between the insertion slits.
According to this structure, because the parts to be fixed to the housing are inserted at both sides of the housing in the back and forth direction, effective reinforcement can be attained along an entire area in the back and forth direction. Furthermore, the part of the housing (the restraining part) interposed between both the parts to be fixed to the housing can effectively restrain the parts to be fixed to the housing from both the back and the forth.
In addition, by constructing the two reinforcing metal plates so that they may have a shape identical to each other, mass production can be promoted, and the cost can be reduced.
Especially, provided that the two reinforcing metal plates have a symmetrical shape as seen in the lateral direction of the housing, common use of the two reinforcing metal plates can be realized while maintaining a balanced structure.
Although there are no specific means according to the invention for fixing the parts to be fixed to the housing to the relevant housing, the parts to be fixed to the housing may be provided on their surfaces with hooks which are adapted to be engaged with inner walls of the slits. By engaging the hooks in this manner, reliable fixation can be attained with a simple structure.